This invention relates to continuous monitoring of the condition of a filter.
Filters are utilized in a wide variety of applications. Many industrial applications require the filtering of process gases, for example.
One concern that has always existed in a filtering environment is the desire to know the condition of the filter to ensure that it is performing its filtering task. Filters can become loaded or plugged and no longer permit effective filtering. Filters can also rupture and leak, permitting unfiltered material to pass through or around the filter. A need exists for a system of monitoring the condition of the filter.
In accordance with one aspect of the present invention, a monitoring system is provided for use with a filter assembly having a filter, an inflow path for a material to flow to the filter and an outflow path for material to flow from the filter. The monitoring system includes a flow meter to sense volume flow, a differential pressure sensor to sense the pressure difference in the inflow path and the outflow path, a pressure sensor for the flow and a temperature sensor to sense the temperature of the flow. A computer takes input from the flow meter, differential pressure sensor and temperature sensor to calculate the permeability of the filter. This provides an indication of filtering effectiveness.
In accordance with another aspect of the present invention, the monitoring system computer has an alarm which is activated by a condition of the permeability being above a predetermined value, below a predetermined value or changing at a rate exceeding a predetermined value. In accordance with another aspect of the present invention, the control is a computer that allows remote monitoring and control of the system.